From patchwork Tue Feb 8 01:25:39 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Hou Tao X-Patchwork-Id: 12738061 X-Patchwork-Delegate: bpf@iogearbox.net Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 80CA2C433EF for ; Tue, 8 Feb 2022 01:47:57 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233071AbiBHBr4 (ORCPT ); Mon, 7 Feb 2022 20:47:56 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:58288 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S236493AbiBHBZx (ORCPT ); Mon, 7 Feb 2022 20:25:53 -0500 Received: from szxga03-in.huawei.com (szxga03-in.huawei.com [45.249.212.189]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 3351FC06109E for ; Mon, 7 Feb 2022 17:25:50 -0800 (PST) Received: from dggpeml500025.china.huawei.com (unknown [172.30.72.54]) by szxga03-in.huawei.com (SkyGuard) with ESMTP id 4Jt4xp24h2zdZTS; Tue, 8 Feb 2022 09:22:38 +0800 (CST) Received: from huawei.com (10.175.124.27) by dggpeml500025.china.huawei.com (7.185.36.35) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2308.21; Tue, 8 Feb 2022 09:25:46 +0800 From: Hou Tao To: Alexei Starovoitov , Daniel Borkmann , Martin KaFai Lau CC: Ard Biesheuvel , Yonghong Song , Andrii Nakryiko , Zi Shen Lim , Will Deacon , Catalin Marinas , , , Subject: [PATCH bpf-next v3 2/2] bpf, arm64: calculate offset as byte-offset for bpf line info Date: Tue, 8 Feb 2022 09:25:39 +0800 Message-ID: <20220208012539.491753-3-houtao1@huawei.com> X-Mailer: git-send-email 2.27.0 In-Reply-To: <20220208012539.491753-1-houtao1@huawei.com> References: <20220208012539.491753-1-houtao1@huawei.com> MIME-Version: 1.0 X-Originating-IP: [10.175.124.27] X-ClientProxiedBy: dggems703-chm.china.huawei.com (10.3.19.180) To dggpeml500025.china.huawei.com (7.185.36.35) X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: bpf@vger.kernel.org X-Patchwork-Delegate: bpf@iogearbox.net insn_to_jit_off passed to bpf_prog_fill_jited_linfo() is calculated in instruction granularity instead of bytes granularity, but bpf line info requires byte offset, so fixing it by calculating ctx->offset as byte-offset. bpf2a64_offset() needs to return relative instruction offset by using ctx->offfset, so update it accordingly. Fixes: 37ab566c178d ("bpf: arm64: Enable arm64 jit to provide bpf_line_info") Signed-off-by: Hou Tao --- arch/arm64/net/bpf_jit_comp.c | 16 +++++++++++----- 1 file changed, 11 insertions(+), 5 deletions(-) diff --git a/arch/arm64/net/bpf_jit_comp.c b/arch/arm64/net/bpf_jit_comp.c index 68b35c83e637..aed07cba78ec 100644 --- a/arch/arm64/net/bpf_jit_comp.c +++ b/arch/arm64/net/bpf_jit_comp.c @@ -164,9 +164,14 @@ static inline int bpf2a64_offset(int bpf_insn, int off, /* * Whereas arm64 branch instructions encode the offset * from the branch itself, so we must subtract 1 from the - * instruction offset. + * instruction offset. The unit of ctx->offset is byte, so + * subtract AARCH64_INSN_SIZE from it. bpf2a64_offset() + * returns instruction offset, so divide by AARCH64_INSN_SIZE + * at the end. */ - return ctx->offset[bpf_insn + off] - (ctx->offset[bpf_insn] - 1); + return (ctx->offset[bpf_insn + off] - + (ctx->offset[bpf_insn] - AARCH64_INSN_SIZE)) / + AARCH64_INSN_SIZE; } static void jit_fill_hole(void *area, unsigned int size) @@ -1087,13 +1092,14 @@ static int build_body(struct jit_ctx *ctx, bool extra_pass) const struct bpf_insn *insn = &prog->insnsi[i]; int ret; + /* BPF line info needs byte-offset instead of insn-offset */ if (ctx->image == NULL) - ctx->offset[i] = ctx->idx; + ctx->offset[i] = ctx->idx * AARCH64_INSN_SIZE; ret = build_insn(insn, ctx, extra_pass); if (ret > 0) { i++; if (ctx->image == NULL) - ctx->offset[i] = ctx->idx; + ctx->offset[i] = ctx->idx * AARCH64_INSN_SIZE; continue; } if (ret) @@ -1105,7 +1111,7 @@ static int build_body(struct jit_ctx *ctx, bool extra_pass) * instruction (end of program) */ if (ctx->image == NULL) - ctx->offset[i] = ctx->idx; + ctx->offset[i] = ctx->idx * AARCH64_INSN_SIZE; return 0; }